An absorbent article such as a sanitary towel, an incontinence protector or a pantyliner, which article has essentially an elongate shape, with a longitudinal direction and a transverse direction, and has two end portions and a central portion situated between the end portions.
Conventional absorbent articles of the type mentioned above usually have a flat shape. Since the female pubic region does not have a corresponding flat appearance, problems can occur when applying and wearing such articles. The contact of the article against the body is not optimum, and when a gap develops there is a great risk of leakage. In order to solve this problem, it has been proposed to make the absorbent articles cup-shaped rather than flat. By and large, this shape provides a better fit to the contours of the body. The cup shape is produced, for example, by arranging elastic in the longitudinal edges of the article, or the article is moulded in a cup shape. EP 155,515 describes how an absorbent article is given a cup-shaped appearance by arranging elastic in the longitudinal side edges of the article. WO 96/20679 describes an absorbent article which comprises a resilient component and tensioning member for giving the article a cup-shaped appearance.
A problem with articles of the abovementioned type is that they do not adapt to the anatomy of the user particularly well, but simply have a general cup-shaped appearance. An article shaped in this way does not provide a good fit against the body. In addition, a gap can easily occur between the user""s body and the user""s briefs since most women, during menstruation, wear briefs which are of poor quality from the outset or are of poor quality because they are old ones. Unless either the absorbent article or the briefs are able to maintain a good contact with the user""s body, there is a great risk of menstruation fluid leaking past both the absorbent article and the briefs.
WO 97/07764 discloses an incontinence product having longitudinally extending elastication means providing a longitudinal ridge in the central portion of the product. The product has a generally curved shape in the longitudinal direction and is stated to provide improved body contact in the central area of the product.
EP 0 335 253 discloses an absorbent article which is provided with a deformation element which causes the article to assume a predetermined shape in response to laterally acting forces.
EP 302,523 describes an absorbent article which has a three-dimensional, anatomically designed shape. The article has an end portion of flat or concave shape and an end portion which is provided with an elevation. The flat or concave end portion is intended to be placed outside the user""s mons pubis, and the end portion comprising the elevation is intended to fit the user""s buttocks. The three-dimensional configuration of the article is obtained by folding a fairly stiff absorption body. To make the elevation permanent, the reverse side of the article is provided with an adhesive surface at the end portion which is to present the elevation. When the elevation has been formed, it is maintained with the aid of the adhesive.
A problem with a construction of this type is that the three-dimensional shape can be hard and uncomfortable for the user. Moreover, it is difficult to package and transport a stiff three-dimensional product. It takes up a lot of space during transport and when on sale, and it can be inconvenient for the user to carry around a sanitary towel or an incontinence protector which cannot be folded and which therefore cannot be concealed in the hand or, at worst, cannot even be fitted in a handbag.
The object of the invention is to remedy the abovementioned problems and to make available an absorbent article which provides a good fit against the user""s body, and which article is comfortable to use and easy to transport.
According to the invention, an article of the type discussed in the introduction, and in which the problems associated with previously known articles of this kind have been eliminated, is distinguished by the fact that elastic is arranged on the article and gives the article a cup-shaped part at one end portion and a ridge-like elevation at the other end portion.
According to one embodiment of the invention, the elastic is arranged in a loop in the end portion which has a cup-shaped part. Arranging the elastic in a loop contributes to giving the end portion its cup shape.
According to another embodiment of the invention, the elastic is arranged as a continuous thread or band running through the entire article.
In order to further improve the anatomical fit against the user""s body for an article with a ridge-like elevation which extends across both the central portion of the article and across one end portion thereof, according to one embodiment of the invention the ridge-like elevation in the end portion has a steeper inclination towards the centre line of the article than does the ridge-like elevation in ad the central portion, as seen from a long side of the article.
According to one embodiment of the invention, the elastic in the central portion is arranged in an essentially straight line along the centre line of the article.
According to a further embodiment of the invention, the elastic is arranged as a continuous thread or band running in a loop through the entire article. In this case, the elastic has two halves which in the longitudinal direction are arranged symmetrically around the centre line of the article. The continuous band or thread can be laid overlapping, i.e. with the halves crossing each other, at the transition between the end portion which has the cup-shaped part and the central portion, an at the transition between the central portion and the end portion which has the ridge-like elevation.
According to yet another embodiment of the invention, the article can have at least one fold line. Such a fold line can be arranged on the underside of the article below the ridge-like elevation in the end portion, in order to facilitate the shaping of the ridge-like elevation.
The abovementioned problems are solved by means of the present invention. This is achieved by the fact that elastic is arranged on the article and gives the article a cup shape at one end portion and a ridge-like elevation at the other end portion. When an article according to the invention is placed on the user with the cup-shaped end portion towards the front, that is to say over the mons pubis, and with the ridge-like end portion towards the back, that is to say towards the user""s bottom, the article will fit naturally to the user""s anatomy and will therefore by itself also come to lie fully against the user""s body. The cup shape of the front end portion will surround the mons pubis during use, and the ridge-like elevation of the rear end portion will fit in the cleft between the user""s buttocks. In this way, sealing is obtained at the front, which is required in particular when the user leans forwards or is lying on her stomach, and also sealing at the rear, in particular when the user leans backwards or is lying on her back. Thus, this design affords considerably better protection against leakage than does a generally cup-shaped appearance of an absorbent article which is not fully adapted to the user""s genitals.
An absorbent article according to the invention has a top side and an underside, the top side being liquid-permeable and the underside being liquid-impermeable. The liquid permeability and liquid impermeability, respectively, are usually obtained by the respective side being provided with a layer which is liquid-permeable or liquid-impermeable. The liquid-permeable top side of the article is intended during use to be directed towards the user, and the liquid-impermeable underside is intended during use to be directed away from the user. It is the top side of the article which will have a cup-shaped part at one end portion, a ridge-like elevation at the other end portion, and, if appropriate, a ridge-like elevation in the central portion.
The central portion also preferably has a ridge-like elevation. Because the anatomical shapes are different at the different areas of the user""s body against which the rear end portion and central portion are to fit, the ridge-like elevation of the end portion has a steeper inclination in relation to the centre line of the sanitary towel than does the ridge-like elevation of the central portion. The centre line of the sanitary towel signifies an imaginary line which is placed in the longitudinal direction of the sanitary towel, at an equal distance from both long sides of the sanitary towel. While the elevation of the central portion can be flat or incline very slightly in relation to the centre line, it is important that the elevation of the end portion slopes more steeply in relation to the centre line to ensure that the sanitary towel will fit the cleft between the user""s buttocks.
Since the user""s vestibule will be the part of the body which bears against the centre portion, the central portion of the article should have a cross-section with an elevation at the centre. An elevation in the central portion can be extremely important for preventing leakage, since the sanitary towel can take up the menstruation fluid even as it leaves the body. Since the space which is to be filled by the elevation on the central portion has the approximate shape and size of half a walnut, then, according to the invention, more absorption material can also be placed in the area around the elastic in the central portion. It is also possible to place a further separate absorption body on top of the surface of the sanitary towel at its central portion. A further alternative is to let the two elastic threads run slightly away from each other across the central portion. In this way a wider elevation is obtained which is better adapted to the user""s vestibule.
The fact of an elevation being flat means that it essentially follows a centre line through the article when the latter is considered from one long side. That is to say that the centre line and elevation are parallel as seen from one long side of the article. The fact of an elevation sloping in relation to the centre line when the article is considered from a long side means that the centre line and the elevation form an angle between each other. The greater the angle, up to 90xc2x0, the greater is the inclination of the elevation. If the angle of the elevation of the end portion in relation to the centre line is 45xc2x0, for example, and the angle of the elevation of the central portion is 20xc2x0, then the elevation of the end portion slopes more than that of the central portion. The ridge-like elevations of the central portion and of the end portion advantageously consist of a single continuous elevation of varying inclination. However, for reasons of comfort, some users may object to having an elevation in the central portion, and for this reason it may sometimes be appropriate to omit such an elevation.
As has been described above, the three-dimensional anatomical configuration of the article according to the present invention is obtained by means of the article being provided with elastic. By elastic we mean material which exhibits such elasticity that it can be stretched to an elongation of at least 100% of its unstretched, relaxed length, that is to say to a length which is at least twice its unstretched length, and can return, after the stretching force is released, to at most a 10% elongation of its original unstretched length. The elastic material can consist of natural rubber, synthetic rubber or a mixture thereof, styrene block polymers, polyurethane rubber, elastic polyesters or elastic polyolefins.
The elastic can advantageously be arranged between the surface layer of the article and the layer lying nearest the surface layer, that is to say the intake layer or absorption layer. It is also possible, however, to arrange the elastic between other material layers, for example between the intake layer of the article and its absorption layer. The elastic can also be arranged with different tensioning in different parts in order to obtain different inclinations of the elevations in the central and end portions.
The elastic thread or band can also be laid in different ways in order to obtain different effects. The elastic is advantageously arranged along a longitudinal centre line on the end portion which has the ridge-like elevation. As has already been mentioned, the central portion too can have a ridge-like elevation. The elastic in the central portion is expediently arranged in an essentially straight line along the centre line of the article. The embodiments with elastic along the centre line can advantageously be combined with the different variants of elastication in the cup-shaped end portion.
According to one embodiment of the invention, the elastic is arranged in a U-shape in the end portion which has a cup-shaped appearance. That is to say the elastic broadly speaking follows the outer contour of the end portion, and the opening of the U-shape faces the central portion of the article. According to yet another embodiment of the invention, the elastic is arranged in two mirror-image loops which each follow the outer contour of the long sides of the end portion which has the cup-shaped part.
The elastic in the end portions and in the centre portion can consist of a single continuous loop, with the outer ends in the end portion which has the ridge-like elevation. Alternatively, the elastic can consist of two elastic threads which run in mirror image in the longitudinal direction of the article. In this case, the elastic in the end portion having the cup shape can be arranged in an essentially complete circle. Alternatively, the elastic in the end portion having the cup shape can have the shape of a semi-circle, where that part of the end portion nearest the short side of the article does not have any elastic. As with the above-described circle shape, the semi-circle is not complete either, as it consists of the two elastic loops.
In the case where the elastic consists of a continuous loop, then, in the central portion of the article and in the end portion having the ridge-like elevation, it can run in two parallel thread parts. Alternatively, the loop of elastic can be laid overlapping at one or more points. For example, the loop can be laid overlapping at the transition between the central portion and the end portion which has the cup-shaped part. The loop of elastic can also be laid overlapping a second time at the transition between the central portion and the end portion which has the ridge-like elevation. By crossing the loop of elastic, an even better adaptation to the different parts of the user""s anatomy can be obtained.
To ensure that the elastic will be able to shape the article, the components included in the article should be relatively soft and pliable. A three-dimensional article which is produced by shaping a stiff material may be felt by the user to be hard and uncomfortable. An advantage of obtaining the three-dimensional nature with the aid of elastic instead of by shaping a stiff material is that a softer and more pliable, anatomically shaped article is obtained. In addition, a still further improved adaptation to the body can be achieved by using the elastic together with soft materials. Such an article is resilient and is more pliable and can therefore adapt in cases where the original shape of the article does not have a completely perfect anatomical configuration. Such fine adjustment is not possible with a stiff article. An elastic three-dimensional article also follows the user""s movements more readily than does a stiff article. Moreover, it is difficult to package and transport a stiff three-dimensional article. An article according to the invention provided with elastic is advantageously folded in three parts at the time of packaging and therefore takes up a small amount of space during transport and at the point of sale. It is also an advantage when the user wishes to carry the article around, since it is easy to conceal in the hand, in a pocket or a handbag. The article can of course be folded in another way, for example it can be folded in two or four parts. Rather than creating problems, as in the case of stiff articles, it is an advantage to fold an article which comprises elastic. The folding relieves the elastic during storage, which means that the useful life of the elastic increases considerably.
The absorbent article according to the invention advantageously has a surface layer intended to be directed towards the body, a reverse layer, and an absorption layer situated between the surface layer and the reverse layer. The article can also have an intake layer in order to increase the rate of intake, which layer is arranged between the surface layer and the absorption layer. It may be useful to provide the article with so-called fold lines. These fold lines have two purposes. On the one hand, they can stiffen a soft material so that, for example, the cup shape in the one end portion is maintained, or so that the central portion does not become creased under the forces from the user""s thighs. On the other hand, the fold lines can provide controlled deformation of the article, that is to say the article is folded in a manner appropriate to the application. This means, for example, that the end portion having the ridge-like elevation does not collapse and become a valley under pressure from the sides, but instead it retains the ridge-like elevation against the user""s body, which elevation fits in against the buttocks. If the fold lines are arranged on the underside of the article, a controlled deformation is obtained along the fold lines and the article is folded so that the parts of the underside of the article, to the side of a fold line, are pushed towards each other when the article is subjected to pressure from the user""s thighs.
For this purpose, that is to say for obtaining controlled deformation, the fold lines can be produced, for example, by compression or removal of absorption material. The important point is to create a density in the area under the elastic which is different from the density in the surrounding areas. In this way, the area where the elastic is arranged will lift and form an elevation on the top side of the article. If the purpose of arranging fold lines is to give stability and firmness to the article, the fold lines must be arranged on the top side of the article. In this case, removal of material is not appropriate, but instead only compression, or other stiffening measures for creating the fold lines. Removing material would weaken the article and defeat the purpose.
The absorbent article can be secured in a conventional manner to the user""s underwear with the aid of adhesive, for example. The adhesive can be arranged across the reverse side of the article, either along the margins or completely covering it. It is most advantageous, however, if the adhesive is arranged only in the end portions of the article. Such a construction allows the central portion to move freely and take up the menstruation fluid nearer its point of discharge from the body. A further alternative means of securing the article is to provide it with securing wings along each long side of the article. Examples of securing wings are found in EP 134,086. These securing wings are provided with adhesive surfaces which can be secured to the user""s underwear. That is to say, the rest of the article is not provided with adhesive; In this way, an article is obtained with good securing properties and at the same time with good movement ability. Instead of adhesive, it is possible to use mechanical securing members such as friction fasteners or snap fasteners.